Carb/jetting

[Zbskater400]

Hey guys I bought the34mm Keihin PJ Carb and not sure what it comes with for jets and I currently needed a carb regardless and was wondering what to do for jetting once I receive it. The mods I have now are +3mm crank it is bored over a little bit but forget how much not sure if that matters.. I have a fmf header and toomey silencer.. with the lid open. Also have block off kit. Anyone recommend where to start with the jetting ?

 

[MURPH]

Whats the temperature and elevation where you live?

 

[Zbskater400]

Whats the temperature and elevation where you live?

I live in Massachusetts not sure of elecation but temperature Is around 75-85 degrees

 

[Zbskater400]

Whats the temperature and elevation where you live?

3500 for elevation

 

[Awk08]

3500 for elevation

so you're hovering above Mt. Greylock ????........ LOL

Mount Greylock is the highest natural point in Massachusetts at 3,491 feet


always jet for the lowest elevation you may possibly ride at, it requires the richest jetting.
and be prepared to increase jetting for colder temps come fall/winter.
you may get away without rejetting the stock carb/mods, you will not with this carb and mods


starting points for that carb/your mods:

45/48/50 pilots
DGH or CEL needle (CEL for lower elevations, I run a DGH/middle clip @ 1800')
148 thru 155 mains

unless you're at sea level, the lower (leaner) suggestions above should be close for your current engine mods and that FMF pipe, but start large and work down to be safe.
read up on airscrew/pilot tuning in the carb section and plug chops for the main

 

[Zbskater400]

so you're hovering above Mt. Greylock ????........ LOL

Mount Greylock is the highest natural point in Massachusetts at 3,491 feet


always jet for the lowest elevation you may possibly ride at, it requires the richest jetting.
and be prepared to increase jetting for colder temps come fall/winter.
you may get away without rejetting the stock carb/mods, you will not with this carb and mods


starting points for that carb/your mods:

45/48/50 pilots
DGH or CEL needle (CEL for lower elevations, I run a DGH/middle clip @ 1800')
148 thru 155 mains

unless you're at sea level, the lower (leaner) suggestions above should be close for your current engine mods and that FMF pipe, but start large and work down to be safe.
read up on airscrew/pilot tuning in the carb section and plug chops for the main

Haha thank you... I'm not a jetting expert but what do you mean DGH and CEL for needle ? I haven't gotten the carb yet but it's brand new and the standard main jet is 152 so you suggest for the main 148 through 155? And does it matter what kind of jets I use or do I need keihin jets or can I use the mikuni ones from jetsrus?

 

[MURPH]

The needle at the bottom of the slide is what he is talking about.they come in different sizes and marked with 3 letters like cel or dgh.
You have to use keihin jets. Mikuni are a lot smaller and won't fit. Buy genuine keihin jets